BACKGROUND:In an effort to reduce periprosthetic joint infections (PJIs) following total hip arthroplasty (THA) and total knee arthroplasty (TKA), extended oral antibiotic prophylaxis has gained national popularity. Given conflicting literature on the topic, the aim of this study was to determine if prescription of oral antibiotics at the time of primary arthroplasty was associated with a reduced risk of PJI at one year. METHODS:All patients who underwent primary THA or TKA from January 1, 2016, to November 1, 2024, were included from a large national database. Patients who received at least 48 hours of postoperative oral cefadroxil or cephalexin were matched 1:5 to those who did not receive postoperative antibiotics using propensity scores based on age, sex, body mass index, diabetes, chronic kidney disease, discharge disposition, and procedure type. The primary outcome was PJI within one year postoperatively. A total of 170,016 patients were included, and 28,336 (16.7%) received postoperative antibiotics. RESULTS:The 1-year PJI rate was higher among patients prescribed antibiotics than those who were not (2.3 versus 1.1%, P < 0.001). After adjusting for risk factors, antibiotic prescription remained associated with an increased odds of PJI (odds ratio (OR) 2.02, 95% confidence interval (CI) 1.85 to 2.22). This was observed for low-risk patients (OR 2.75, 95% CI 2.24 to 3.37), but not high-risk patients (OR 1.40, 95% CI 0.94 to 2.10). When stratified by procedure, antibiotic use was associated with higher infection rates after TKA (2.5 versus 1.0%; OR 2.62, 95% CI 2.27 to 3.03) and after THA (2.0 versus 1.3%; OR 1.43, 95% CI 1.23 to 1.67). CONCLUSIONS:Extended postoperative oral antibiotics after primary THA and TKA have become increasingly common. However, this database study showed no reduction in 1-year PJI rates or risk among those who received them, despite accounting for key risk factors.

Introduction The popularity of modular dual mobility (MDM) acetabular components has increased. Concerns have been raised about the potential for corrosion related complications in these modular implants. The purpose of this study was to prospectively monitor serum ion levels in a series of patients with a modular dual mobility system. Methods Twenty-six patients with the Zimmer Biomet G7 DM construct were enrolled and followed for a minimum of one year. Serum cobalt, chromium, and titanium levels were obtained prior to six-weeks postoperatively and at one and two-years postoperatively. Five-year labs were obtained if previous labs were elevated. Results At 0-6 weeks postoperatively, 4/26 patients had mildly elevated cobalt levels (1-2.8 μg/L) and 2/26 had mildly elevated chromium levels (1.6, 2.0 μg/L). None of the 19 patients showed elevated cobalt levels at one or two years, while 4/19 reported mildly elevated chromium levels (1.1-1.3 μg/L) at one-year with a slight decrease (1-1.4 μg/L) at two-years. No patients at any time point had metal ion levels exceeding the initial early threshold of 5 μg/L. No patient was symptomatic and no MRIs were indicated or obtained. Discussion In this series of a specific modular DM system, the early mildly elevated cobalt levels in four patients all subsequently normalized. Chromium was mildly elevated in four patients through year two. While these findings are reassuring in the short term as mildly elevated chromium (<2 μg/L) has not been associated with clinical toxicity, additional follow-up is needed to establish the long-term safety and efficacy of this specific modular DM implant.

BACKGROUND:Coronal plane deformity in total knee arthroplasty (TKA) can introduce major variability in difficulty between cases based on the type and degree of deformity. The purpose of this study was to compare the energy expenditure of TKA in varus and valgus knees. METHODS:There were 85 patients undergoing primary, elective cemented TKA who were prospectively enrolled, and various demographic and surgical variables were collected. Surgeon physiologic parameters were collected via a smart garment that recorded heart rate variability (beats per minute), minute ventilation (mL/minute), and energy expenditure (kcal). Patients who had coronal plane deformities of various degrees were stratified into different groups based on severity: mild varus (N = 31), moderate/severe varus (N = 28), mild valgus (N = 17), and moderate/severe valgus (N = nine). A coronal plane deformity of 10° was the threshold for moderate/severe deformity. Analysis of variance models were used to compare demographics and surgeon physiologic stress between groups. There were differences in age and sex between cohorts (P < 0.05), whereas other demographics were comparable (P > 0.05). RESULTS:Energy expenditure was significantly different across deformities, with valgus knees and increased deformity having the highest expenditure (P < 0.001). Heart rate variability and minute ventilation did not differ across cohorts (P = 0.23). In the regression models, energy expenditure remained significantly higher with mild (P = 0.017) and moderate/severe valgus (P = 0.001) compared to mild varus. Heart rate variability was also significantly increased in these groups (P = 0.03). CONCLUSIONS:Surgeons expend varying degrees of energy during TKA depending on the type and degree of deformity. Total knee arthroplasty in the setting of severe valgus deformity is associated with the most physiologic demand for the surgeon. These data provide quantifiable measures for the degree of case difficulty, which is pertinent for proper compensation for appropriate work.

BACKGROUND:The impacts of load transfer between the collar of modern triple-tapered collared hip stems and the femoral calcar remain unknown. The aim of this study was to determine whether the calcar remodels in response to stress loading or stress shielding in the setting of a well-fixed modern triple-tapered collared stem. METHODS:We conducted a retrospective review of patients from two institutions who underwent primary direct anterior total hip arthroplasty using collared cementless stems, with a minimum 1-year follow-up (n = 182). Statistical analyses were performed to determine associations between patients who demonstrated calcar resorption compared to those who did not. The mean follow-up was 2.3 years (range, one to 6.2), and the mean patient age was 64.2 years (range, 18 to 83). RESULTS:Calcar remodeling, more specifically resorption, occurred in 144 of 182 patients (79.1%). In patients who had resorption, the mean initial postoperative calcar width was 5.9 mm (standard deviation (SD), 1.89), decreasing to a mean final width of 3.3 mm (SD, 1.84). The mean initial postoperative collar overhang was 0.8 mm (SD, 1.44), increasing to a mean final collar overhang of 3.4 mm (SD = 2.6). CONCLUSIONS:Our results demonstrate that 79.1% of the patients who undergo primary total hip arthroplasty with a well-fixed triple-tapered collared cementless stem exhibit calcar resorption in the form of both calcar thinning and increasing collar overhang. These findings suggest that collared stems primarily achieve metaphyseal fixation. While the collar may decrease axial and rotational forces early on, the collar likely provides minimal load transfer to the calcar with stem ingrowth. Clinical implications of calcar thinning in the setting of a collared stem are yet to be fully understood. Future study of this finding is warranted.

BACKGROUND:Although the gold standard for treatment of periprosthetic joint infection (PJI) is a two-stage exchange, patients may elect to retain a well-functioning spacer. The aim of this retrospective review was to evaluate the survivorship, complications, and patient-reported outcome measures (PROMs) of retained articulating total knee arthroplasty (TKA) spacers with patellar component replacement. METHODS:All PJI patients from a tertiary care academic center who received a balanced, articulating metal-on-polyethylene TKA spacer with patellar component replacement were reviewed. After the stage-one spacer, all patients were offered a second-stage exchange within six months, with some electing to retain their spacers beyond one year. Reoperations, recurrent infections, periprosthetic fractures, and PROMs were compared between scheduled second-stage revisions within 6 months and retained spacers beyond one year. Independent t-tests were used for comparisons. A total of 48 patients were included, with 23 undergoing scheduled stage-two revision and 25 electing to retain their spacer beyond one year. In the retained-spacer cohort, one died from an aseptic etiology 47 months postoperatively. Of the 24 living patients, the mean follow-up was 29 months (SD = 19 months). RESULTS:Of the 25 patients in the retained-spacer cohort, five underwent stage-two reimplantation for aseptic loosening of the spacer (none catastrophic), of which one patient (4%) had reinfection after reimplantation. There were no other reinfections, dislocations, periprosthetic fractures, or reoperations that occurred in the retained-spacer cohort. Although not significantly different, 17% (four patients) of the scheduled stage-two cohort had infection recurrence compared to 4% in the retained-spacer cohort. There were no differences in final PROMs between cohorts. CONCLUSIONS:Patients who retained well-balanced, articulating TKA spacers had low infection recurrence, no catastrophic failures, and comparable PROMs to those undergoing scheduled two-stage revision for PJI. Well-balanced articulating metal-on-polyethylene spacers may offer an alternative to two-stage revision in select patients.

BACKGROUND:The outcome of periprosthetic joint infections (PJIs) is not only contingent on treatment strategy and host factors, but also on the infecting organism. Corynebacterium, a genus of gram-positive bacterium, is uncommonly implicated in PJIs, but represents a challenge when present, as it commonly demonstrates resistance to often-used antibiotics. Given the limited data available, we sought to report on our institution's historical experience with managing PJI of the hip or knee due to Corynebacterium. METHODS:A retrospective review was conducted of all total hip and knee arthroplasties performed at our institution from 2016 to 2023 for PJI in which the Corynebacterium genus was identified. Demographic, surgical, and clinical outcomes data were collected. Overall, 18 patients were identified who had a mean age of 65 years, and there was a predominance of women (94.4%). Patients, on average, had 4.9 prior surgeries. RESULTS:Surgical treatment of the Corynebacterium PJI included single-stage revision (n = five, irrigation and debridement (n = two), resection arthroplasty (n = one), and two-stage revision (n = 10). Overall, five cases (27.8%) were polymicrobial infections. Most cases received multiagent treatment (61.1%) administered in a concurrent (90.9%) fashion. The average antibiotic duration was 6.5 weeks. The majority (57.9%) of patients had a prior PJI, and all but one for which data were unavailable, was infected with a multidrug-resistant strain of Corynebacterium. In total, 13 patients had tetracycline-resistant strains of Corynebacterium, and no cases demonstrated vancomycin resistance. At final follow-up (mean = 2.9 years, SD = 2.8), 16 patients had never undergone amputation, 15 had no reinfection, and 12 patients were alive. CONCLUSIONS:Corynebacterium-associated PJIs represent a unique subset of disease that can be challenging to manage, in part due to its antibiotic resistance profile. However, with close collaboration between surgical and infectious disease teams, reasonable outcomes can be expected.

INTRODUCTION:Osteoporosis widely affects the aging population and often leads to debilitating fragility fractures. Dual-energy X-ray absorptiometry scans are important for osteoporosis screening and treatment among aging women to prevent fragility fractures; however, disparities exist across populations. This study analyzed these disparities to help reduce screening inequalities to prevent complications of osteoporosis. METHODS:A sample was used from the 2018, 2020, and 2022 U.S. Medical Expenditure Panel Survey of women who responded about screening dual-energy X-ray absorptiometry utilization. Logistic regression modeling was used to determine the associations between social determinants of health, particularly between limited English proficiency and screening dual-energy X-ray absorptiometry utilization. Two models-social determinants of health and social determinants of health + limited English proficiency-were generated utilizing these variables modified by the addition of the variable of English proficiency. RESULTS:Half of the 10,079 respondents without osteoporosis (48%, n=4,851) reported undergoing a dual-energy X-ray absorptiometry scan with a median age of 69 (50-85) years. Low income; lower education; Black, Asian, Hispanic race/ethnicity; and limited English proficiency were significantly associated with not receiving a screening dual-energy X-ray absorptiometry scan. Hispanic women had a 55% decreased likelihood of receiving a screening dual-energy X-ray absorptiometry scan (OR=0.450, 95% CI=0.365, 0.554, p<0.001) compared with non-Hispanic White women, although this lost statistical significance when accounting for limited English proficiency (OR=0.732, 95% CI=0.521, 1.029, p=0.073). CONCLUSIONS:The results demonstrate significant social determinants of health disparities in dual-energy X-ray absorptiometry screening for osteoporosis. The effect is modified, specifically the association of race/ethnicity, when limited English proficiency is included as a risk factor. Awareness of these disparities is important for primary care and other providers to deliver equitable prevention and treatment opportunities for osteoporosis.

Background There remains a lack of literature on how patient demographics and modifiable factors influence patient-reported outcome recovery curves following primary total knee arthroplasty (TKA). This study assessed how these factors influence the progression of patient-reported outcomes following primary TKA and to create visual aids to assist in perioperative counseling. Methods Prospective multicenter data from 2196 patients who underwent primary TKA were analyzed using generalized estimating equations to model longitudinal Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) scores collected preoperatively and at 1, 3, 6, and 12 months postoperatively. Models were adjusted for repeated measures within patients and included interaction terms between time and demographic or modifiable risk factors to assess differences in recovery trajectories. Stratifications included age, sex, race, ethnicity, body mass index, smoking status, preoperative opioid use, and preoperative activity level. Clinical significance was defined using a minimal clinically important difference of 6.25 points. Results Patients who were less than 50 years old, women, black, Hispanic, underweight, or consumed opioids preoperatively all demonstrated significantly lower KOOS JR scores throughout the postoperative recovery curve. However, the rate at which women recovered was significantly greater at each postoperative time point. Black patients recovered at a similar rate compared to white patients, which was also the case for Hispanic vs non-Hispanic patients. While patients who used opioids preoperatively had lower overall KOOS JR scores, they demonstrated significantly quicker recoveries for the first 3 months postoperatively, but these differences became insignificant thereafter. Conclusions Several patient demographics and modifiable risk factors impact patient’s recovery following primary TKA, which can assist in counseling patients regarding recovery following primary TKA.

Fixation choice (polymethyl-methacrylate bone cement or cementless implants) in total knee arthroplasty (TKA) varies widely across surgeons, reflecting differences in clinical judgment. While traditional statistical approaches are commonly used to study surgical decision-making, they may be limited in capturing complex and multifactorial relationships inherent in such data. This study evaluates how different supervised machine learning (SML) algorithms characterize fixation choice and prioritize predictors, rather than developing a clinical decision-support tool. We analyzed data from the multicenter Patient-Centered Outcomes Research Institute (PCORI)-funded Comparative Effectiveness of Pulmonary Embolism Prevention after Hip and Knee Replacement (PEPPER) trial, linked with the American Hospital Association Annual Survey. Adult patients undergoing elective primary TKA for osteoarthritis between December 2016 and May 2024 were included. The primary outcome was the binary classification of cemented versus cementless fixation. Five models were evaluated (logistic regression, LASSO, support vector machine, XGBoost, and Random Forest). Model performance was assessed using discrimination, precision–recall performance, calibration, and F1 score within a nested cross-validation framework. All confidence intervals were estimated using surgeon-clustered bootstrap resampling. Permutation importance was used for cross-model feature comparison, and SHapley Additive exPlanations (SHAP) were applied to interpret the best-performing model. Among 7848 patients treated by 140 surgeons at 29 hospitals, 85.8

BACKGROUND:Surgeons use cementless unicompartmental knee arthroplasty (UKA) as a joint-preserving alternative to total knee arthroplasty. However, cementless UKA survivorship and revision data remain fragmented. To address this gap, we systematically reviewed (1) survivorship of cementless UKAs reported at time points ≤ five years and ≥ 10 years and (2) the revision indications across implant types. METHODS:The PubMed and EMBASE databases were searched to identify relevant studies. Inclusion criteria comprised cementless UKA devices with available survivorship and revision data. Study quality was assessed using the modified Coleman Methodology Score and the Journal of Bone and Joint Surgery Level of Evidence criteria. RESULTS:We identified 27 studies on seven cementless device designs. Medial UKAs accounted for most implants (81.5%). Studies with 5-year time points or less reported a median survivorship of 96.1%. At time points ≥ 10 years, survivorship decreased to 92.0% (P = 0.01). The most frequent revision indications included instability (16%), progression of osteoarthritis (14%), and aseptic loosening (11%). In some cases, the indications for revision depended on the device: one device was associated with polyethylene-related complications (57%), while a blade-anchored device was frequently revised following loosening (63%). CONCLUSIONS:Success was device specific, with three of four cementless UKA devices exceeding 95% survivorship within five years and three of five achieving at least 92% survivorship after 10 years. It remains unclear whether cementless UKA devices can decrease revision rates comparable to total knee arthroplasty, promoting increased utilization.

INTRODUCTION:With an aging population in the United States, the demand for joint arthroplasty procedures continues to rise. As patient volumes increase in arthroplasty clinics, the documentation burden for each clinic day also grows, creating a demand for tools that can help alleviate this workload. Artificial intelligence (AI)-powered tools, such as automated charting assistants, may enhance provider efficiency by reducing documentation time. This study evaluates whether implementing an AI scribe in an orthopaedic clinic decreases documentation time for providers. METHODS:A retrospective, nonexperimental analysis was conducted after the adoption of a commercially available Health Insurance Portability and Accountability Act (HIPAA)-compliant AI scribe software tool. Active electronic medical record time per clinic day was measured for a team comprising one orthopaedic surgeon, one physician associate, and one orthopaedic surgery fellow. Resident physicians were excluded because of frequent rotation changes. RESULTS:Before AI implementation, providers saw an average of 38.7 patients (±2.2) over 34 clinic days, compared with 39.9 patients (±2.3) over 27 clinic days after implementation (P = 0.043). Total active EMR time per clinic day significantly decreased by 26.1% after implementation (after: 339.1 ± 78.7 vs. before: 458.8 ± 95.6 minutes; P < 0.0001). Average EMR time per patient decreased by 35.3% (after: 7.7 ± 2.9 vs. before: 11.9 ± 2.5 minutes; P < 0.0001). Total EMR time per clinic day (P = 0.0046) and per patient (P = 0.0002) demonstrated a significant, continual decline throughout the postimplementation period. CONCLUSION:The use of an AI-powered scribing assistant markedly reduced documentation time in an orthopaedic clinic, enhancing provider efficiency. These findings suggest a promising strategy for alleviating documentation burden, potentially improving clinic workflow as patient volume increases. Larger, multicenter studies are needed to confirm these benefits and explore long-term effects on provider workload and patient care.

BACKGROUND:Iliopsoas impingement (IPI) is an underrecognized complication following total hip arthroplasty (THA), typically attributed to anterior acetabular component overhang. As modern implants have shifted toward collared stem designs, an overhanging femoral collar may also contribute to IPI. We aimed to determine whether the degree of femoral stem collar overhang is associated with IPI in direct anterior approach THA. METHODS:We retrospectively reviewed 985 primary direct anterior THAs performed with triple-tapered collared femoral stems at a single academic center. All IPI cases were identified using diagnosis codes and surrogate markers (iliopsoas injections, metal artifact reduction sequence magnetic resonance imaging, or arthroscopic tenotomy) and then confirmed through chart review. Radiographic measurements included femoral collar overhang, neck height, and anterior cup overhang at six weeks, with collar overhang reassessed at one year. Collar overhang was analyzed continuously and dichotomously using a 3-mm cutoff determined by receiver operating curve analysis. Multivariable logistic regressions assessed the association of collar overhang with IPI, adjusting for age, sex, and body mass index. RESULTS:Within one year of surgery, 4.8% of hips (47 of 985) met criteria for IPI. At 1-year follow-up, the mean collar overhang was significantly greater in the impingement group (1.90 versus 1.42 mm, P = 0.036), and a larger proportion had overhang ≥ three mm (29.8 versus 13.7%, P = 0.003). In multivariable analysis, collar overhang ≥ three mm was associated with more than double the odds of IPI (odds ratio 2.2, P = 0.024). Cup overhang was minimal and not significantly different in either group. CONCLUSIONS:In direct anterior THA with collared femoral stems, increased collar overhang was associated with IPI. A threshold of greater than three mm may identify hips at elevated risk. Further research is needed to reduce IPI risk.

BACKGROUND:Rapidly progressive osteoarthritis (RPOA) has been associated with hip corticosteroid injections (CSIs), but may also mimic septic arthritis, which demonstrates similar erosive findings. This retrospective review evaluated a consecutive series of patients who had RPOA of the hip following CSI who underwent total hip arthroplasty (THA) and assessed outcomes and potential infection screening implications. METHODS:All radiographic reports concerning RPOA were retrospectively identified at a single academic referral center from January 2014 to January 2023. A total of 4,279 reports were identified, and after removing duplicates, 2,175 patients were individually chart-reviewed. The occurrence of RPOA was defined as chondrolysis of at least 2 mm per year or 50% of joint space loss within 1 year of a CSI of the hip. Patients who had prior malignancy, septic arthritis, oral corticosteroid use, or femoral head osteonecrosis were excluded. RESULTS:Ultimately, 81 patients, who had a mean follow-up time of 2 years, were identified who had undergone THA for RPOA following CSI. Preoperative infectious workup was performed in 31 patients who have inflammatory markers and eight patients who have a hip aspiration based on surgeon discretion. The mean aspiration cell counts and polymorphonuclear percentages were 1,410.8 (SD = 1,574.2) and 52.3% (SD = 23.3), respectively. Cultures were negative in all aspirations. All eight patients had negative aspirations and negative intraoperative cultures, and none developed periprosthetic joint infection (PJI). There were two patients who developed PJI within 1 month following THA, and neither underwent a preoperative infectious workup with labs or aspirations. No other patients underwent repeat surgery. CONCLUSIONS:The occurrence of RPOA of the hip following CSI was associated with an estimated 2.5% risk of PJI. Preoperative screening with inflammatory markers and possible joint aspiration should be considered prior to THA for patients who have CSI-related RPOA.

Background Mobile-bearing (MB) total knee arthroplasty (TKA) designs have proposed biomechanical benefits, including improved patellar tracking and reduction in polyethylene wear. Yet, prior work using the American Joint Replacement Registry (AJRR) has demonstrated an increased risk of all-cause revision with MB-TKA. We therefore utilized the AJRR to further characterize reasons for the increased risk of revision with MB-TKA compared to fixed-bearing (FB) TKA designs. Methods All primary TKAs reported to AJRR from January 2012 to March 2020 in patients 65 years and older who had a minimum 2-year follow-up were analyzed. The TKAs were categorized as MB or FB and as posterior stabilized (PS) or cruciate retaining (CR) femoral designs. Inverse probability weighted cause-specific Cox models were used to determine the risk of all-cause revision, revision for mechanical loosening, and all-cause revision, excluding mechanical loosening, accounting for gender, age, Charlson Comorbidity Index, and year of procedure. Results A total of 445,701 TKAs were identified; 203,224 were CR (193,662 FB, 9,662 MB), and 242,477 were PS (212,801 FB, 29,676 MB) TKAs. Compared to FB-TKA, those who had PS MB-TKA were associated with an increased risk for all-cause revision (hazard ratio [HR]: 1.2, 95% confidence interval [CI] 1.1 to 1.2, P < 0.001) and revision for mechanical loosening (HR: 2.1, 95% CI 1.8 to 2.5, P < 0.001). Compared to FB-TKA, those with CR MB-TKA were not associated with increased risk for all-cause revision (HR: 1.1, 95% CI 0.9 to 1.5, P = 0.27), but were associated with increased risk of revision for mechanical loosening (HR: 1.8, 1.3 to 2.5, P < 0.001). Excluding mechanical loosening, there was no difference in the risk of revision for PS (HR: 1.0, 95% CI 1.0 to 1.1, P = 0.30) or CR (HR: 1.0, 95% CI 0.9 to 1.2, P = 0.81). Conclusions When clarifying the reasons for the increased risk of revision associated with MB-TKA, the hazard appears to be significantly increased specifically for mechanical loosening in both PS and CR MB-TKA designs. Additional studies are needed to examine what unique design features associated with MB-TKA are leading to this increased risk of mechanical loosening. Level of evidence Therapeutic level III.

BACKGROUND:Conversion total knee arthroplasty (TKA) requires increased preoperative planning, surgical time, and perioperative resources; yet, there is currently no separate procedural code for conversion TKA as there is for conversion total hip arthroplasty (THA). The purpose of this study was to compare energy expenditure for the surgeon when performing primary, conversion, and revision TKA/THA. METHODS:Surgery was performed on 179 arthroplasty patients prospectively by five surgeons. There were 77 primary TKA, 10 conversion TKA, 18 revision TKA, 58 primary THA, four conversion THA, and 12 revision THA patients. Energy expenditure of the surgeon's institution was recorded via a smart garment. Demographic variables and energy expenditure were compared between cohorts using analysis of variance tests. RESULTS:Overall, TKA patients were similar in age, sex, and laterality. Body mass index varied among TKA groups, with conversion and primary being lower than revision TKA (P= 0.018). There were no differences in body mass index and sex in THA patients. The conversion THA cohort was younger than the primary and revision THA cohorts (P= 0.015). Conversion TKA (467.2 ± 219.4 calories) required 152% higher energy expenditure than primary TKA (308.0 ± 109.2 cal), but less than revision TKA (703.8 ± 368.0 cal; P< 0.001). Conversion THA (523.8 ± 117.9 cal) required 143% higher energy expenditure than primary THA (365.2 ± 112.5 cal), but less than revision THA (846.2 ± 435; P< 0.001). CONCLUSION:Conversion TKA is associated with significantly more physiologic stress for a surgeon. The increased energy expenditure seen in conversion TKA relative to primary TKA mimics the increase seen in conversion THA, which does have a conversion procedural code. This study highlights the need for payment reform to reflect the actual work done by arthroplasty surgeons.

Background: Cementless total knee arthroplasty (TKA) has seen a resurgence due to advancements in tibial implant fixation. However, most femoral components remained unchanged, typically being cobalt chromium with nonenhanced porous ingrowth surfaces. The literature is sparse concerning radiographic and clinical outcomes related to the femoral component in uncemented designs. Methods: This retrospective, single-center study included 268 cementless TKA. Radiolucent lines were evaluated using the Knee Society Radiographic Evaluation and Scoring System. Clinical outcomes were measured using the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR). Linear regression modeling was performed to analyze the relationship between KOOS JR and the presence of radiolucent lines. Results: Radiolucent lines were significantly more prevalent at the femoral bone–implant interface (177 of 268; 66.0%) compared to the tibial bone–implant interface (114 of 268; 42.5%) (P < .0001). There was no significant correlation between the presence of radiolucent lines and KOOS JR. Aseptic loosening was identified as the leading cause of revision surgery (6 of 268; 2.2%), with femoral component loosening accounting for 5 out of 6 aseptic revisions. Conclusions: Femoral radiolucent lines were common in this study. Although femoral component loosening was the most frequent cause of revision, these lines did not generally necessitate revision or correlate with poorer patient-reported outcomes. Thus, radiolucent lines do not inherently indicate clinical failure or reduced patient satisfaction. There was only one case of tibial component loosening, suggesting that the current design features achieve robust fixation, while the prevalence of femoral radiolucent lines and failures suggests that further enhancements to the femoral implant may be necessary.

BACKGROUND:Currently, two-stage revision total hip arthroplasty is the gold standard in managing periprosthetic joint infection (PJI) of the hip; however, complications are common, including instability. The purpose of this study was to determine how alterations in limb length during a stage 1 articulating spacer affect dislocation rates of the stage 2 revision. METHODS:A retrospective study of consecutive patients who underwent two-stage revision total hip arthroplasty for PJI between December 2013 and December 2022 was performed. We measured limb length as the perpendicular distance from the trans-teardrop line to the apex of the lesser trochanter after stage 1 articulating spacer implantation. Independent t-tests and logistic regression were used to compare limb lengths following stage 1 spacers between patients who did and did not dislocate after stage 2 implantation. Overall, 147 patients who underwent staged revisions for the treatment of PJI were identified. The cohort was 59% women who had a mean age of 60 years (range, 25 to 84 years) and an average follow-up time of 2.7 years (range, 1.0 to 9.1 years). RESULTS:The dislocation rates after stage 1 and stage 2 were 3.0 and 11.7%, respectively. Limb length did not impact dislocation rates of the articulating stage 1 spacers (P = 0.71), but patients who sustained a dislocation following stage 2 were lengthened significantly more at stage 1 implantation (8.5 ± 15.9 versus 0.8 ± 11.8 mm, P = 0.033). Additionally, the odds of dislocation after stage 2 increased by 7% with each mm lengthened during stage 1 (odds ratio = 1.07, 95% confidence interval: 1.01 to 1.13). CONCLUSIONS:During a stage 1 articulating spacer of the hip, limb length restoration is often disregarded, which can result in overlengthening that may necessitate subsequent shortening during stage 2 reconstruction. This study demonstrates that overlengthening of an articulating stage 1 hip spacer can place the patient at an increased risk of dislocation following stage 2 reconstruction.

BACKGROUND:Patterns in revision total hip arthroplasty (THA) have continued to evolve throughout the decades. We investigated whether these trends could vary by practice location and analyzed the indications and incidence of revision and "complex" revision THA at our isolated regional academic referral center over the past two decades. We hypothesized that our regional referral center has attracted an increasing level of complexity in revision THA cases over time. METHODS:A retrospective chart review was conducted on all revision THAs from 2000 to 2023. Indications and details of revision THA were recorded. Using previously published methods, cases were classified as "complex" if they included extended trochanteric osteotomy, triflange, augments, or a cup-cage construct. Trends in indications and complexity were compared between the periods 2000 to 2004 (early) and 2019 to 2023 (recent) using Chi-square tests. RESULTS:A total of 2,793 revision THAs were performed from 2000 to 2023 (an average of 116 revisions/year). Comparing 2000 to 2004 with 2019 to 2023, the average annual number of revision THA increased from 89.8 to 157.6. The total volume of complex revisions was higher (average 13.2 cases/year historically versus 20.2 recently). Specifically, the annual averages of extended trochanteric osteotomy increased from 6.8 to 9, augments from 0.8 to 4.2, triflange from 2.2 to 2.8, and cup-cage constructs from 5.4 to 5.8. Indications changed significantly over time, with more often loosening historically (39%) and infection or reimplantation more recently (35.9%) (P < 0.0001). CONCLUSIONS:At a large regional academic referral center, we have seen a major increase in the total number of revision THA cases with a concomitant increase in "complex" cases from 2000 to 2023. Indications for revision THA have transitioned from loosening historically to infection or reimplantation more recently.

BACKGROUND:Beginning July 1, 2024, the Centers for Medicare and Medicaid Services (CMS) began mandating at least 50% institutional compliance of patient-reported outcome-based performance measures (PRO-PMs) for Medicare fee-for-service patients undergoing inpatient, elective arthroplasty. The purpose of this study was to quantify a single institution's PRO-PM capture rates before the deadline and determine risk factors for noncompliance. METHODS:There were 2,692 patients who underwent primary elective hip and knee arthroplasty at a single institution from 2021 to 2022. Demographic and compliance data (PRO-PM collected in the preoperative window within 90 days before surgery and the postoperative window at 365 ± 60 days) was recorded. Compliance was further analyzed after the introduction of a text-based service designed to collect PRO-PMs. Multivariable analysis was performed to determine independent risk factors for noncompliance with completing PRO-PMs. RESULTS:Overall, less than half of patients (N = 1,329, 49.1%) completed preoperative PRO-PMs within 90 days of surgery, and only 25.8% of patients (N = 695) completed postoperative PRO-PMs at 305 to 425 days. Compliance with both pre- and postoperative PRO-PMs was 14.1% (N = 380). Compliance with both pre- and postoperative reporting increased from 7.9 to 19.6% following the introduction of a text-based platform reminding patients to complete the surveys. Risk factors for noncompliance include non-English primary language (odds ratio (OR) 4.96, 95% confidence interval [1.43 to 17.21], P = 0.012), higher comorbidity burden (OR 1.1 [1.03 to 1.18], P = 0.005), and not receiving a text reminder to complete the survey (OR 2.84 [2.15 to 3.76], P < 0.001). CONCLUSIONS:The low rate of compliance with the new Centers for Medicare and Medicaid Services mandate for PRO-PM collection, even at an academic center with a high desire to collect and study patient outcomes with PRO-PMs, suggests the mandate may be overly burdensome, though initiatives designed to increase patient engagement may help improve compliance.